Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 1 | /* |
| 2 | * LM8333 keypad driver |
| 3 | * Copyright (C) 2012 Wolfram Sang, Pengutronix <w.sang@pengutronix.de> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version 2 of the License. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/irq.h> |
| 13 | #include <linux/i2c.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | #include <linux/input/matrix_keypad.h> |
| 16 | #include <linux/input/lm8333.h> |
| 17 | |
| 18 | #define LM8333_FIFO_READ 0x20 |
| 19 | #define LM8333_DEBOUNCE 0x22 |
| 20 | #define LM8333_READ_INT 0xD0 |
| 21 | #define LM8333_ACTIVE 0xE4 |
| 22 | #define LM8333_READ_ERROR 0xF0 |
| 23 | |
| 24 | #define LM8333_KEYPAD_IRQ (1 << 0) |
| 25 | #define LM8333_ERROR_IRQ (1 << 3) |
| 26 | |
| 27 | #define LM8333_ERROR_KEYOVR 0x04 |
| 28 | #define LM8333_ERROR_FIFOOVR 0x40 |
| 29 | |
| 30 | #define LM8333_FIFO_TRANSFER_SIZE 16 |
| 31 | |
Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 32 | #define LM8333_NUM_ROWS 8 |
Dmitry Torokhov | 1932811 | 2012-05-10 22:37:08 -0700 | [diff] [blame] | 33 | #define LM8333_NUM_COLS 16 |
| 34 | #define LM8333_ROW_SHIFT 4 |
Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 35 | |
| 36 | struct lm8333 { |
| 37 | struct i2c_client *client; |
| 38 | struct input_dev *input; |
| 39 | unsigned short keycodes[LM8333_NUM_ROWS << LM8333_ROW_SHIFT]; |
| 40 | }; |
| 41 | |
| 42 | /* The accessors try twice because the first access may be needed for wakeup */ |
| 43 | #define LM8333_READ_RETRIES 2 |
| 44 | |
| 45 | int lm8333_read8(struct lm8333 *lm8333, u8 cmd) |
| 46 | { |
| 47 | int retries = 0, ret; |
| 48 | |
| 49 | do { |
| 50 | ret = i2c_smbus_read_byte_data(lm8333->client, cmd); |
| 51 | } while (ret < 0 && retries++ < LM8333_READ_RETRIES); |
| 52 | |
| 53 | return ret; |
| 54 | } |
| 55 | |
| 56 | int lm8333_write8(struct lm8333 *lm8333, u8 cmd, u8 val) |
| 57 | { |
| 58 | int retries = 0, ret; |
| 59 | |
| 60 | do { |
| 61 | ret = i2c_smbus_write_byte_data(lm8333->client, cmd, val); |
| 62 | } while (ret < 0 && retries++ < LM8333_READ_RETRIES); |
| 63 | |
| 64 | return ret; |
| 65 | } |
| 66 | |
| 67 | int lm8333_read_block(struct lm8333 *lm8333, u8 cmd, u8 len, u8 *buf) |
| 68 | { |
| 69 | int retries = 0, ret; |
| 70 | |
| 71 | do { |
| 72 | ret = i2c_smbus_read_i2c_block_data(lm8333->client, |
| 73 | cmd, len, buf); |
| 74 | } while (ret < 0 && retries++ < LM8333_READ_RETRIES); |
| 75 | |
| 76 | return ret; |
| 77 | } |
| 78 | |
| 79 | static void lm8333_key_handler(struct lm8333 *lm8333) |
| 80 | { |
| 81 | struct input_dev *input = lm8333->input; |
| 82 | u8 keys[LM8333_FIFO_TRANSFER_SIZE]; |
| 83 | u8 code, pressed; |
| 84 | int i, ret; |
| 85 | |
| 86 | ret = lm8333_read_block(lm8333, LM8333_FIFO_READ, |
| 87 | LM8333_FIFO_TRANSFER_SIZE, keys); |
| 88 | if (ret != LM8333_FIFO_TRANSFER_SIZE) { |
| 89 | dev_err(&lm8333->client->dev, |
| 90 | "Error %d while reading FIFO\n", ret); |
| 91 | return; |
| 92 | } |
| 93 | |
Alan Cox | 954bd6d | 2012-06-27 12:02:07 +0100 | [diff] [blame] | 94 | for (i = 0; i < LM8333_FIFO_TRANSFER_SIZE && keys[i]; i++) { |
Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 95 | pressed = keys[i] & 0x80; |
| 96 | code = keys[i] & 0x7f; |
| 97 | |
| 98 | input_event(input, EV_MSC, MSC_SCAN, code); |
| 99 | input_report_key(input, lm8333->keycodes[code], pressed); |
| 100 | } |
| 101 | |
| 102 | input_sync(input); |
| 103 | } |
| 104 | |
| 105 | static irqreturn_t lm8333_irq_thread(int irq, void *data) |
| 106 | { |
| 107 | struct lm8333 *lm8333 = data; |
| 108 | u8 status = lm8333_read8(lm8333, LM8333_READ_INT); |
| 109 | |
| 110 | if (!status) |
| 111 | return IRQ_NONE; |
| 112 | |
| 113 | if (status & LM8333_ERROR_IRQ) { |
| 114 | u8 err = lm8333_read8(lm8333, LM8333_READ_ERROR); |
| 115 | |
| 116 | if (err & (LM8333_ERROR_KEYOVR | LM8333_ERROR_FIFOOVR)) { |
| 117 | u8 dummy[LM8333_FIFO_TRANSFER_SIZE]; |
| 118 | |
| 119 | lm8333_read_block(lm8333, LM8333_FIFO_READ, |
| 120 | LM8333_FIFO_TRANSFER_SIZE, dummy); |
| 121 | } |
| 122 | dev_err(&lm8333->client->dev, "Got error %02x\n", err); |
| 123 | } |
| 124 | |
| 125 | if (status & LM8333_KEYPAD_IRQ) |
| 126 | lm8333_key_handler(lm8333); |
| 127 | |
| 128 | return IRQ_HANDLED; |
| 129 | } |
| 130 | |
| 131 | static int __devinit lm8333_probe(struct i2c_client *client, |
| 132 | const struct i2c_device_id *id) |
| 133 | { |
| 134 | const struct lm8333_platform_data *pdata = client->dev.platform_data; |
| 135 | struct lm8333 *lm8333; |
| 136 | struct input_dev *input; |
| 137 | int err, active_time; |
| 138 | |
| 139 | if (!pdata) |
| 140 | return -EINVAL; |
| 141 | |
| 142 | active_time = pdata->active_time ?: 500; |
| 143 | if (active_time / 3 <= pdata->debounce_time / 3) { |
| 144 | dev_err(&client->dev, "Active time not big enough!\n"); |
| 145 | return -EINVAL; |
| 146 | } |
| 147 | |
| 148 | lm8333 = kzalloc(sizeof(*lm8333), GFP_KERNEL); |
| 149 | input = input_allocate_device(); |
| 150 | if (!lm8333 || !input) { |
| 151 | err = -ENOMEM; |
| 152 | goto free_mem; |
| 153 | } |
| 154 | |
| 155 | lm8333->client = client; |
| 156 | lm8333->input = input; |
| 157 | |
| 158 | input->name = client->name; |
| 159 | input->dev.parent = &client->dev; |
| 160 | input->id.bustype = BUS_I2C; |
| 161 | |
Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 162 | input_set_capability(input, EV_MSC, MSC_SCAN); |
| 163 | |
Dmitry Torokhov | 1932811 | 2012-05-10 22:37:08 -0700 | [diff] [blame] | 164 | err = matrix_keypad_build_keymap(pdata->matrix_data, NULL, |
| 165 | LM8333_NUM_ROWS, LM8333_NUM_COLS, |
| 166 | lm8333->keycodes, input); |
| 167 | if (err) |
| 168 | goto free_mem; |
Wolfram Sang | 0bf25a4 | 2012-04-03 13:39:44 -0700 | [diff] [blame] | 169 | |
| 170 | if (pdata->debounce_time) { |
| 171 | err = lm8333_write8(lm8333, LM8333_DEBOUNCE, |
| 172 | pdata->debounce_time / 3); |
| 173 | if (err) |
| 174 | dev_warn(&client->dev, "Unable to set debounce time\n"); |
| 175 | } |
| 176 | |
| 177 | if (pdata->active_time) { |
| 178 | err = lm8333_write8(lm8333, LM8333_ACTIVE, |
| 179 | pdata->active_time / 3); |
| 180 | if (err) |
| 181 | dev_warn(&client->dev, "Unable to set active time\n"); |
| 182 | } |
| 183 | |
| 184 | err = request_threaded_irq(client->irq, NULL, lm8333_irq_thread, |
| 185 | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, |
| 186 | "lm8333", lm8333); |
| 187 | if (err) |
| 188 | goto free_mem; |
| 189 | |
| 190 | err = input_register_device(input); |
| 191 | if (err) |
| 192 | goto free_irq; |
| 193 | |
| 194 | i2c_set_clientdata(client, lm8333); |
| 195 | return 0; |
| 196 | |
| 197 | free_irq: |
| 198 | free_irq(client->irq, lm8333); |
| 199 | free_mem: |
| 200 | input_free_device(input); |
| 201 | kfree(lm8333); |
| 202 | return err; |
| 203 | } |
| 204 | |
| 205 | static int __devexit lm8333_remove(struct i2c_client *client) |
| 206 | { |
| 207 | struct lm8333 *lm8333 = i2c_get_clientdata(client); |
| 208 | |
| 209 | free_irq(client->irq, lm8333); |
| 210 | input_unregister_device(lm8333->input); |
| 211 | kfree(lm8333); |
| 212 | |
| 213 | return 0; |
| 214 | } |
| 215 | |
| 216 | static const struct i2c_device_id lm8333_id[] = { |
| 217 | { "lm8333", 0 }, |
| 218 | { } |
| 219 | }; |
| 220 | MODULE_DEVICE_TABLE(i2c, lm8333_id); |
| 221 | |
| 222 | static struct i2c_driver lm8333_driver = { |
| 223 | .driver = { |
| 224 | .name = "lm8333", |
| 225 | .owner = THIS_MODULE, |
| 226 | }, |
| 227 | .probe = lm8333_probe, |
| 228 | .remove = __devexit_p(lm8333_remove), |
| 229 | .id_table = lm8333_id, |
| 230 | }; |
| 231 | module_i2c_driver(lm8333_driver); |
| 232 | |
| 233 | MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>"); |
| 234 | MODULE_DESCRIPTION("LM8333 keyboard driver"); |
| 235 | MODULE_LICENSE("GPL v2"); |